Windows only: Microsoft Outlook add-in SaveAllAttachments does just what its name implies; it saves all the attachments from selected messages to a folder of your choosing, optionally deleting them from the message.

Once you've installed SaveAllAttachments and restarted Outlook, you can use the add-in by simply selecting some messages and clicking the button. You'll be prompted for a folder, asked if you want to delete the original attachments, and the files will be swiftly saved into a folder—a very useful solution for quickly reducing the size of your PST file.